I have posted about this before from GM
The driver’s outside rearview mirror on some 2020-2022 Corvettes may have poor operation and appearance,
including numerous lines shown in the mirror and a dim reflection at all times. (Fig. 14)
The poor appearance caused by the installation of an aftermarket radar detector in the vehicle.
Depending on the installation location, the aftermarket electrical device
may cause higher voltage to the mirror.
If the damaged mirror appearance is shown, check for the installation of a jumper harness to power the radar detector added to the mirror’s X1 connector.
The connector is located behind the front cover of the inside rearview mirror. (Fig. 15)
Disconnecting the jumper harness, and replacing the damaged outside rearview mirror due to the jumper harness, must be authorized by the customer.
Vehicle damage resulting from aftermarket devices is not covered under warranty.
For additional information, refer to Bulletin #21-NA-251.